How to Create a New Pattern in Photoshop CS6
By Barbara Obermeier from Photoshop CS6 All-in-One For Dummies

In Adobe Photoshop Creative Suite 6, you can create your own pattern, basing it on an existing image or one you create yourself. Select a small portion of an image to build an abstract pattern or use a recognizable object to define that object as a pattern stamp. You can use anything, from a logo to your signature, as a pattern.

To create your own pattern, follow these steps:

Open the image that contains the area you want to use as a pattern or create an image from scratch.

Make any modifications to the image to produce the exact pattern that you want.

Use the Rectangular Marquee tool to select the area you want to convert into a pattern.

If you don’t make a selection, Photoshop uses your entire image as a basis for the pattern.

If you’re using a selection to define your pattern, you must use a rectangular selection. You can’t use a feathered selection of any kind.